Speaker 1: Pushkin. You might have noticed that things are a little
Speaker 1: different on Cautionary Tales this year. In twenty twenty four,
Speaker 1: we brought you a new episode every fortnight, But this
Speaker 1: year we are doubling our output. New stories of heart
Speaker 1: thumping peril, mind blowing mistakes, and jaw dropping scandal will
Speaker 1: now be delivered straight to your ears every week. Here's
Speaker 1: on for you right now. Not so very long ago,
Speaker 1: I took my son with me to an amusement park
Speaker 1: to celebrate his twelfth birthday. He's obsessed with roller coasters,
Speaker 1: although usually he just experiences them through the medium of YouTube.
Speaker 1: It's one thing to see the footage someone took from
Speaker 1: the front seat. To actually be there, it's a different thing.
Speaker 1: Riding a roller coaster is a strange kind of fun.
Speaker 1: The volunteering to be terrified for the sake of entertainment,
Speaker 1: and the roller coaster we'd come to ride certainly leans
Speaker 1: into that idea. It's called the smiler. The conceit behind
Speaker 1: the smiler is that people who aren't smiling enough will
Speaker 1: have their lack of a smile corrected by a strange
Speaker 1: Awwellian institution called the Ministry of Joy. The smiler's logo
Speaker 1: is a ghastly grin connecting two hypnotically spiraling eyes. And
Speaker 1: so we went to Alton Towers in England to ride
Speaker 1: the Smiler. The ride doesn't soar in the high curves
Speaker 1: of a classic roller coaster. Instead, it's an imp penetrable
Speaker 1: looking spaghetti tangle of black and yellow, with the knots
Speaker 1: and curls of the roller coaster track intersecting with a
Speaker 1: huge five legged structure, some kind of diabolical machine, decorated
Speaker 1: with a wraparound screen displaying dystopian messages and unsettling graphics.
Speaker 1: It's hard to figure out what goes. Where As we
Speaker 1: waited in line underneath the belly of the thing, we
Speaker 1: gazed up at the tortuous coils of the ride through
Speaker 1: black netting that added to the vibe of a correctional facility,
Speaker 1: but was really to protect us from wallets and phones
Speaker 1: falling out of the pockets of the riders in the
Speaker 1: trains above. And those trains looped and swooped around and
Speaker 1: around above us, two together on different parts of the track,
Speaker 1: diving and rolling around each other like mating birds, but
Speaker 1: there was no bird song. The sound was deafening. A
Speaker 1: night Mayish theme tune like a nursery rhyme from hell,
Speaker 1: the steel roaring as the trains rushed over ahead, so
Speaker 1: close that it seemed we could touch them. And of
Speaker 1: course there were the screams of the riders. They screamed
Speaker 1: and they screamed, and they screamed as the ride turned
Speaker 1: them upside down, over and over and over again, a
Speaker 1: world record fourteen in versions. And as we gazed upon
Speaker 1: the sheer awfulness of the thing, my son turned to
Speaker 1: me and said, Dad, I'm not sure I want to
Speaker 1: go on this ride. And he told me something else, Dad,
Speaker 1: He said, you should do a cautionary tale about the Smiler.
Speaker 1: I'm Tim Harford and this is that cautionary tale. Seventeen
Speaker 1: year old Leah Washington's first big day out with her
Speaker 1: new boyfriend Joe Pugh was a trip to Alton Towers,
Speaker 1: the theme park which is home to the Smiler. Leah
Speaker 1: suggested going on the Sonic Spinball coaster. Joe wasn't convinced.
Speaker 1: Why line up for hours when the ride isn't even
Speaker 1: that good. It was June twenty fifteen. The Smiler itself
Speaker 1: was only a couple of years old, but had quickly
Speaker 1: become an iconic roller coaster ride. So Joe suggested the
Speaker 1: Smiler instead. Now that is a roller coaster worth waiting for.
Speaker 1: Lea was nervous. She'd never been on the Smiler and
Speaker 1: it looks terrifying, but she agreed, and so they patiently
Speaker 1: lined up, edging forward to enjoy their turn. It was
Speaker 1: a windy day that they were sheltered from the worst
Speaker 1: of the gusts as the roller coaster cars swooped and
Speaker 1: screamed above them. The line edged forward, and the minutes
Speaker 1: ticked past half past eleven noon half past twelve. By
Speaker 1: one o'clock, Lea and Joe could see they were close
Speaker 1: to getting onto the Smiler itself, with the diabolical nursery
Speaker 1: tune playing and the lines surrounded by unsettling images of compliant,
Speaker 1: grinning faces. So we queued for a good hour and
Speaker 1: a half. Leah later recalled, and then we got to
Speaker 1: the front and they put us on the front carriage.
Speaker 1: Those words are from a television interview she gave just
Speaker 1: a couple of months later. In the interview, Leah is
Speaker 1: serious but calm. She's a remarkably self possessed young woman.
Speaker 1: She's also missing her left leg Smiler trains are short
Speaker 1: and wide, four rows, four seats in each one. Leah
Speaker 1: and Joe were in the front row. Me and Joe
Speaker 1: got excited being at the front. The front row is
Speaker 1: much sought after. You get the best views, the most excitement,
Speaker 1: the most direct exposure to everything the Smiler has to offer.
Speaker 1: But then we sat down, put the safety bars down.
Speaker 1: Then we were sat for five ten minutes, and then
Speaker 1: we had to get back off because there were technical difficulties.
Speaker 1: That was a bit frustrating. That was Leah warried. Now,
Speaker 1: not really, because all rides break down at some point,
Speaker 1: but you didn't expect anything bad to happen. So Leah
Speaker 1: and Joe stood at the front of the line and
Speaker 1: waited to get back on. The Alton Towers Theme Park
Speaker 1: has dedicated teams of engineers. The park wants to keep
Speaker 1: the rides running smoothly and safely, with a minimum of interruptions.
Speaker 1: The need for safety is obvious enough, but so is
Speaker 1: the need to minimize downtime. There can easily be two
Speaker 1: thousand people in the line to ride the Smiler, and
Speaker 1: Olden Towers doesn't want people saying I queued for two
Speaker 1: hours for the Smiler and I never even got a ride.
Speaker 1: The show must go on, which might explain why. On
Speaker 1: the second of June twenty fifteen, the Smiler was operating
Speaker 1: despite the windy weather. When the roller coaster registered a
Speaker 1: fault and Lear and the other riders were taken off
Speaker 1: the train and asked to wait. Two teams of engineers
Speaker 1: hurried to the scene. The line was only getting longer,
Speaker 1: and two trains were sitting out on the twisting roller
Speaker 1: coaster track full of increasingly anxious passengers, wondering what the
Speaker 1: problem was and whether it was anything to do with
Speaker 1: the gusts of wind. The first team of engineers started
Speaker 1: to diagnose the problem, which was nothing serious, and also
Speaker 1: decided to add a fifth train to the track while
Speaker 1: the ride was suspended. That meant that once the roller
Speaker 1: coaster was operating again, it would accommodate a few more passengers.
Speaker 1: Seven minutes after the fault appeared, the engineers were able
Speaker 1: to bring a train of relieved guests back to the station,
Speaker 1: where they got off and wandered away to enjoy the
Speaker 1: rest of the theme park. A minute after that, another train,
Speaker 1: the last occupied train, arrived and the passengers disembarked. Now
Speaker 1: all four empty trains were safely inside the roller coaster
Speaker 1: station and the fifth train was added. This took another
Speaker 1: five minutes, while Lea and Joe and two thousand people
Speaker 1: behind them waited and wondered what was happening. As the
Speaker 1: fifth train was being added, the roller coaster's electronic system
Speaker 1: flashed up seven more fault codes. Each of them was minor,
Speaker 1: but each of them needed to be acknowledged, checked, and
Speaker 1: then cleared. By now Lea and Joe and the others
Speaker 1: had been waiting nearly twenty minutes to get back on
Speaker 1: the ride, and the engineers sent an empty train around
Speaker 1: the roller coaster just to check that everything was working properly.
Speaker 1: It wasn't. The train went out, but it didn't come back.
Speaker 1: Like many roller coasters, the Smiler operates on a combination
Speaker 1: of gravity and momentum. The trains don't have engines in them. Instead,
Speaker 1: each train is pulled up a long slope by a
Speaker 1: chain lift, then released to run the course of humps
Speaker 1: and loops until finally coasting back into the station. Roller
Speaker 1: coaster the clues in the name, but because the Smiler
Speaker 1: has that world record tangle of fourteen inversions, because it
Speaker 1: stays fairly low level with the tree tops. One chain
Speaker 1: lift hill won't do the job, and so halfway round
Speaker 1: the ride comes one of the defining moments of the
Speaker 1: Smiler experience. There's a second chain lift, and instead of
Speaker 1: being pulled up a long slope, the chain runs vertically. Suddenly,
Speaker 1: your seat tips back so far that your feet are
Speaker 1: higher than your head, and you stared directly up at
Speaker 1: the sky, being hoisted higher and higher up a vertical track.
Speaker 1: But in June twenty fifteen, that test train didn't come
Speaker 1: back because it didn't quite reach the second lift, the
Speaker 1: vertical one. It coasted to a halt just short of
Speaker 1: where the lift chain would engage. Why unclear. The fact
Speaker 1: that it had no passengers meant that it would have
Speaker 1: been a little lighter and carried less momentum. Then there
Speaker 1: were those gusts of wind. Whatever the reason, it wasn't
Speaker 1: quite close enough for the lift chain to finish the journey.
Speaker 1: They were puzzling over this problem. The first team of
Speaker 1: engineers were joined by the second team, a pair of
Speaker 1: electrical engineers. They all huddled together for a brief conference.
Speaker 1: But one thing that doesn't seem to have been mentioned
Speaker 1: was that a fifth train had been added to the
Speaker 1: track anyway, it wasn't hard to figure out what was wrong.
Speaker 1: The ride had sensors which showed that a section of
Speaker 1: track was occupied by a train, that train they had
Speaker 1: just sent out as a test. The engineers could also
Speaker 1: look at CCTV images and see that train stopped just
Speaker 1: shy of the chain lift. Three of the engineers made
Speaker 1: their way down to the track's halfway point at the
Speaker 1: bottom of the vertical lift hill. They put their shoulders
Speaker 1: to the heavy train and started to push until the
Speaker 1: train clicked into the chainlift and up it went, straight
Speaker 1: up the vertical rails before coasting around the remaining loops
Speaker 1: and corkscrews and back to the station. Lear and Joe
Speaker 1: and the rest of the sixteen passengers had been waiting
Speaker 1: for half an hour since being put onto a train
Speaker 1: and then taken off again, with no knowledge of what
Speaker 1: the Smiler engineers had been up to. But at long
Speaker 1: last they were nearly ready to get the passengers back
Speaker 1: onto the ride. Ahead of the train, Lea and the
Speaker 1: others were board, there was another empty train. The engineers
Speaker 1: sent it off around the circuit, and Leah and Joe
Speaker 1: stepped forward to be strapped into the front row of
Speaker 1: the smiler, ready for the ride of a lifetime. Cautionary
Speaker 1: tales will be back after the break. Roller Coasters are
Speaker 1: safer than lots of things people do for fun. They're
Speaker 1: certainly a lot safer than riding in a car, if
Speaker 1: you believe the numbers from the International Association of Amusement
Speaker 1: Parks and Attractions. And why wouldn't you believe them. My
Speaker 1: son and I ran about the same risk in driving
Speaker 1: one hundred miles to Alton Towers and one hundred miles
Speaker 1: back again that we would have faced if we'd ridden
Speaker 1: six hundred roller coasters. So sure, roller coasters are pretty safe,
Speaker 1: but they don't feel safe. They're not meant to feel safe.
Speaker 1: And if you pushed a nervous roller coaster rider to
Speaker 1: think about what might actually be dangerous about a roller coaster,
Speaker 1: they'd probably tell you two things. First, I might fall
Speaker 1: out of my seat, and second, the entire train might
Speaker 1: fall off the track. That makes intuitive sense. The tracks
Speaker 1: look narrow and exposed, and the trains go fast, take
Speaker 1: the perilous curves, and for goodness sake, they go upside down.
Speaker 1: But that's not really the problem. Here are the words
Speaker 1: of Stephen Flanagan, an expert on roller coaster safety. Although
Speaker 1: the public perception of the hazards associated with roller coasters
Speaker 1: may be focused in the danger of a train parting
Speaker 1: company with the track, in reality, the bigger and more
Speaker 1: difficult to resolve issue has always been the hazard of
Speaker 1: trains colliding on the track. When you get on a
Speaker 1: roller coaster like the Smiler, you really don't need to
Speaker 1: worry that the train is going to fall off one
Speaker 1: of those gravity defying loops. You really don't need to
Speaker 1: worry about anything. But if you did feel like worrying
Speaker 1: about something, I don't suggest worrying that your train might
Speaker 1: smash into another train. As Leah and Joe's train moved off,
Speaker 1: a diabolic voice boomed over the speakers join us. Then
Speaker 1: the train plunged into a dark section of track, shocking
Speaker 1: the passengers by flipping upside down and right side up again,
Speaker 1: before emerging into daylight and slowly clanking up the first
Speaker 1: chain lift higher and higher and higher. Ahead of them
Speaker 1: on the Smiler tracks was an empty train, and none
Speaker 1: of the passengers realized that empty train was slowing As
Speaker 1: it approached the top of a loop, the wind was
Speaker 1: still gusting the empty trains were still a little on
Speaker 1: the light side. The train came to a stop, then
Speaker 1: slowly rolled back to settle in a dip. Once Lea
Speaker 1: and Joe's train was released from the lift hill, it
Speaker 1: would take twenty six seconds to loop over to that dip.
Speaker 1: They were less than half a minute from disaster, except
Speaker 1: their train just stopped right at the top of the lift.
Speaker 1: We got to the first lift hill and it got
Speaker 1: stuck at the top. So obviously me and Joe were discussing, Oh,
Speaker 1: this isn't right. Why had the train stopped? Simple. Although
Speaker 1: the Smiler engineers hadn't realized there was a problem, the
Speaker 1: smiler's monitoring system knew perfectly well that there was a
Speaker 1: train stalled out on the track. Automatically, it held Lear
Speaker 1: and Joe's train at the top of the slope, the
Speaker 1: highest point of the Smiler, waiting for the blockage to
Speaker 1: be cleared. Catastrophe had been averted by an automated system.
Speaker 1: So now what. Paul Meal was an expert who became
Speaker 1: fascinated by the mistakes experts make. That was partly an
Speaker 1: intellectual interest of his, but it was also very personal.
Speaker 1: In nineteen thirty five, when Meal was fifteen years old,
Speaker 1: his mother had gone to her doctor with some symptoms
Speaker 1: which the doctor attributed to problems with her inner ear.
Speaker 1: In fact, the cause was a brain tumor. The doctor
Speaker 1: could have diagnosed the tumor by asking some basic questions
Speaker 1: and performing some basic checks, but didn't. A year later,
Speaker 1: the tumor had grown and spread. It was finally diagnosed
Speaker 1: by a different doctor, and Paul Meel's mother died soon after.
Speaker 1: Yiel later wrote this episode of gross medical bungling permanently
Speaker 1: immunized me from the childlike faith in physicians' omniscience that
Speaker 1: one finds among most persons. Meil became an academic researcher
Speaker 1: and a clinical psychologist, and he never lost his curiosity
Speaker 1: about the fallibility of human experts. In his early thirties,
Speaker 1: he published a book that was to become famous, Clinical
Speaker 1: versus Statistical Prediction. The book asked a question, should you
Speaker 1: trust the judgment of an expert doctor, or is it
Speaker 1: better to take a short list of symptoms, feed them
Speaker 1: into a simple flowchart, and do whatever the flowchart says.
Speaker 1: Such a flowchart might have saved his mother. This was
Speaker 1: nineteen fifty four, so we're not talking about pitting human
Speaker 1: experts against sophisticated artificial intelligence, talking about pitting human experts
Speaker 1: against a crude formulaic process, but Meil found that the
Speaker 1: crude formulaic process often beat the humans. Three years later,
Speaker 1: he published an academic article with a punchy follow up question,
Speaker 1: when shall we use our heads instead of the formula?
Speaker 1: It's a question that's much more pressing today than it
Speaker 1: was when he asked it in the nineteen fifties. Computers
Speaker 1: tell managers who to hire and who to fire. They
Speaker 1: tell radiologists whether a shadow on a scan is cancer
Speaker 1: or not. They advised judges on who should be released
Speaker 1: on bail and who should be detained, and they helped
Speaker 1: social services prioritize calls about children at risk. The computers
Speaker 1: they're everywhere, So when should we trust them instead of
Speaker 1: our own judgment? Paul Meill wrote, I find the two
Speaker 1: extreme answers to this question, namely always and never equally unacceptable.
Speaker 1: At Alton Towers, the engineers were about to override the computer.
Speaker 1: That's not always the wrong choice. Sometimes the human is
Speaker 1: right and the computer is wrong. Unfortunately, this wasn't one
Speaker 1: of those times. Lear and Joe and the others had
Speaker 1: waited an hour and a half to get onto the Smiler,
Speaker 1: then another half an hour while the technical fault was resolved.
Speaker 1: Now they were perched precariously at the highest point of
Speaker 1: the ride. A long minute ticked by. Then another excitement
Speaker 1: gave way to waves of anxiety, boredom and annoyance. They
Speaker 1: said over the tannel, we're experiencing technical difficulties. Bear with us.
Speaker 1: They really weren't supposed to be poised and ready to
Speaker 1: roll for such a long time. What was going on?
Speaker 1: The Smilers engineers were trying to figure that out too.
Speaker 1: The Smiler has a simple computer system designed to prevent
Speaker 1: trains from smashing into each other at certain points on
Speaker 1: the track. There are proximity switches which register when a
Speaker 1: train enters a block of track and when it leaves
Speaker 1: it again. If the system thinks a train is on
Speaker 1: a particular block of track, it will automatically prevent the
Speaker 1: train behind it from being released into that block. That's
Speaker 1: what was happening here. Of course, the empty train hadn't
Speaker 1: left the block. In fact, it was still gently penduluming
Speaker 1: backwards and forwards, settling in the valley ahead of Leah
Speaker 1: and Joe's train. So the smiler's computer prevented the occupied
Speaker 1: train behind it from moving forward, leaving Lear and the
Speaker 1: other passengers waiting and waiting at the top of the
Speaker 1: lift hill. Meanwhile, on the ride's control panel, the zone
Speaker 1: stop alarm was activated, notifying the engineers that one train
Speaker 1: was being held because the train ahead hadn't left its
Speaker 1: block of track. Hmm, well, the occupied block was the
Speaker 1: one including the vertical chain lift, where the previous train
Speaker 1: had stalled. It was natural to assume that if a
Speaker 1: second train had stalled, that would be where it was.
Speaker 1: One of the engineers went out to have a look,
Speaker 1: but there was no train at the bottom of the
Speaker 1: vertical lift. As far as he was concerned, then the
Speaker 1: smiler's collision prevention system was just malfunctioning. Probably it hadn't
Speaker 1: reset itself from the train which stalled fifteen minutes before.
Speaker 1: That might seem like a big assumption, but this was
Speaker 1: one of the engineers who arrived after the fifth train
Speaker 1: had been added. He didn't know about it, or if
Speaker 1: someone had mentioned it, it had slipped his mind. So
Speaker 1: he thought there were four trains, and he knew where
Speaker 1: four trains were LEAs at the top of the lift hill.
Speaker 1: And three in the station. If it turned to look
Speaker 1: over his shoulder and looked carefully, he might have seen
Speaker 1: the fifth train valid at the other end of the
Speaker 1: ride through the tangle of roller coaster track. But he
Speaker 1: didn't look, or if he did, he didn't see. At
Speaker 1: the bottom of the vertical chain lift was a control
Speaker 1: panel to reset the block sensors. The engineer performed that reset,
Speaker 1: telling the computer to forget its erroneous belief that there
Speaker 1: was a train stuck on the track. Unfortunately, it wasn't
Speaker 1: the computer which had an erroneous belief, it was the humans.
Speaker 1: Retails will return in a moment. Leah's train has now
Speaker 1: been held at the top of the chain hill for
Speaker 1: six long minutes. There's still a chance the smiler system
Speaker 1: won't release the train without an explicit override from the humans.
Speaker 1: So now the critical decision is with the engineers back
Speaker 1: in the station. But they don't explicitly discuss whether there
Speaker 1: are four trains running or five. They don't send anyone
Speaker 1: out to visually confirm that the whole track is clear, nor,
Speaker 1: it seems, do they look carefully at the CCTV screens.
Speaker 1: The smiler does have lots of CCTV screens very on
Speaker 1: brand for a dystopian roller coaster experience, but the ride
Speaker 1: is such a tangle of track that it's hard to
Speaker 1: see clearly. Right now, the valid train is partly obscured,
Speaker 1: and the engineers don't look carefully enough. Maybe they don't
Speaker 1: look at all. They're all just assuming the computer must
Speaker 1: be wrong, so they decide to override it. The smiler's
Speaker 1: system still won't release one train into a section where
Speaker 1: it knows another train is stationary, but it doesn't know
Speaker 1: about the stationary train anymore because its memory of the
Speaker 1: obstacle has been deliberately reset. Leah recalled it just set
Speaker 1: back off without any warning. At last, Leah's train starts
Speaker 1: to roll down from the lift hill and accelerate into
Speaker 1: loop after loop after loop. Twenty six seconds away is
Speaker 1: a stationary train. They were fine, We were going around
Speaker 1: loops and everything. We just came round this corner and
Speaker 1: I saw this car and I'm like, oh my god,
Speaker 1: this isn't good. Paul Neil, the clinical psychologists who pose
Speaker 1: the question about when we should follow the formula and
Speaker 1: when we should use our heads, didn't have an easy answer,
Speaker 1: but he did suggest a rule of thumb. If you,
Speaker 1: as the human, know something that the algorithm doesn't know
Speaker 1: that the algorithm can't know, that's a reason to think
Speaker 1: about overruling the computer. But when investigators later looked into
Speaker 1: the causes of the Smiler accident, they noticed that the
Speaker 1: engineers had a patchy knowledge about how the ride's false
Speaker 1: alarms actually worked. This meant they were often puzzled when
Speaker 1: the alarms went off. They'd do some safety checks and
Speaker 1: reset the system, but exactly why the alarm had sounded
Speaker 1: was sometimes a mystery, so the engineers regarded the alarm
Speaker 1: system as capricious and unreliable. If the engineers had been
Speaker 1: better trained, they'd have understood the logic of the alarm
Speaker 1: system and would have been able to think clearly about
Speaker 1: when to override it and when not to. Paul Meel
Speaker 1: warned us, if you're going to overrule the computer, you'd
Speaker 1: better have a reason to think you know something that
Speaker 1: it doesn't. But to do that, you need to have
Speaker 1: a firm understanding of how the computer works. The Smilers
Speaker 1: engineers didn't. As Leah and Joe and the others looped
Speaker 1: upside down and saw the empty train ahead of them,
Speaker 1: they had only a moment to brace for the shattering impact.
Speaker 1: The train wasn't going especially far. You'd probably walk away
Speaker 1: from a car crash at that speed, but unlike cars,
Speaker 1: roller coasters don't have crumple zones. Leah was right at
Speaker 1: the front with no protection, and as metal smashed into metal,
Speaker 1: the two trains locked together and rocked backwards and forwards
Speaker 1: twelve times, with the legs of the front row passengers
Speaker 1: crushed between them. The next thing I remember was the
Speaker 1: screaming and the blood. There was so much of it.
Speaker 1: The metal of the safety bars had folded into our bodies,
Speaker 1: said Leah later. All I wanted was to hold Joe's hand,
Speaker 1: but when I looked down at it, I could see
Speaker 1: there was no way I could. His little finger was
Speaker 1: hanging off his left hand, and the middle finger on
Speaker 1: the other was broken. All the front row passengers had
Speaker 1: horrendous leg wounds. Both Joe's kneecaps were shattered. Leah's injuries
Speaker 1: were even worse. I started getting pain. I couldn't feel
Speaker 1: my toes, Leah remembered, and I started to look at
Speaker 1: my legs. My left leg was all pushed up. They
Speaker 1: were snarled up in a tangle of metal at a
Speaker 1: forty five degree angle twenty feet above the ground, and
Speaker 1: the Smile operators were apparently still confused because it took
Speaker 1: seventeen minutes before anybody called for the emergency services. Up
Speaker 1: on the coaster, Leah nearly died from blood loss, but
Speaker 1: an air ambulance flew in blood for an emergency transfusion
Speaker 1: twenty feet above ground. Later, she stopped breathing, but the
Speaker 1: medics reaching her from precarious ladders and hoists managed to
Speaker 1: resuscitate her. Once she was released from the train. Hours later,
Speaker 1: Leah was flown to hospital, slipping in and out of consciousness.
Speaker 1: She woke up twenty four hours later. I realized two
Speaker 1: things were missing, my boyfriend and my entire left leg.
Speaker 1: The doctors told her sorrowfully that they had faced a
Speaker 1: choice her leg or her life, so they took the leg.
Speaker 1: The woman sitting next to her on the roller coaster,
Speaker 1: Vicki Balch, also had her leg amputated. Joe Pew was
Speaker 1: elsewhere in the hospital. He and several other passengers also
Speaker 1: suffered severe injuries, all because the Smilers engineers hadn't double
Speaker 1: checked when the computer told them there was a train
Speaker 1: out on the track. Given what she's been through, Leah
Speaker 1: Washington is doing incredibly well. She's something of an Instagram influencer,
Speaker 1: posting videos of herself learning to walk, learning to run,
Speaker 1: learning to ski, or selfies of her looking fabulous in
Speaker 1: a bikini. They look like a lot of Instagram self is,
Speaker 1: in fact, except that she's looking fabulous in a bikini
Speaker 1: with an artificial leg. Joe never regained the use of
Speaker 1: one finger, but his knees were covered eventually, and the
Speaker 1: pair are still together. Leah is now missus Washington Pew
Speaker 1: after she and Joe tied the knot in twenty twenty four.
Speaker 1: But that happy ever after ending so nearly didn't happen.
Speaker 1: At that moment when Leah was unconscious and trapped in
Speaker 1: crumpled metal twenty feet above the ground, when a team
Speaker 1: of paramedics on hoists were trying to get her breathing
Speaker 1: started again, it was touch and go. The medics later
Speaker 1: told her if the weather had been any colder, she
Speaker 1: wouldn't have made it. In a world where we're surrounded
Speaker 1: by automatic systems, statistical formulas, algorithms, and computers, we're going
Speaker 1: to have to get better at deciding when to trust
Speaker 1: them and when to overrule them. There will never be
Speaker 1: a hard and fast rule for when to do that,
Speaker 1: But if you're thinking of ignoring the computer, it's wise
Speaker 1: to have a logical reason to think you know better.
Speaker 1: The Smiler engineers didn't. When investigators picked over the disaster,
Speaker 1: they concluded that there was nothing wrong with the roller
Speaker 1: coaster itself, nor with the automatic alarm system. It was modern,
Speaker 1: well designed, and functioned exactly as intended. The problems emerged
Speaker 1: from the working practices of the engineering team. It was
Speaker 1: partly the fact that the engineers didn't fully understand their
Speaker 1: own safety alarms, and it was also that nobody in
Speaker 1: particular was in charge of the process of resetting the
Speaker 1: Smiler after the very first fault alarm. There were the
Speaker 1: ride operators, the first engineering team, and the second engineering team,
Speaker 1: all trying to make decisions. There were loose, informal conversations
Speaker 1: in which nobody had a full overview of what was
Speaker 1: going on. There was no written process for working systematically
Speaker 1: through a checklist before resetting the ride, and there was
Speaker 1: no formal assignment of responsibility as to who had the
Speaker 1: authority to override the automatic system and under what circumstances.
Speaker 1: This lack of a formal process was critical. Without it,
Speaker 1: the engineering team could just assume that the track was clear.
Speaker 1: With a formal process, someone would have been clearly responsible
Speaker 1: for checking. Fifteen months after the accident, a judge called
Speaker 1: it an obvious shambles involving lack of communication and double checking,
Speaker 1: which could and should easily have been avoided by a
Speaker 1: written system of working, including a single overall supervisor. Automatic
Speaker 1: systems can help us avoid accidents and make better decisions,
Speaker 1: but Paul Meele's question will never go away. When should
Speaker 1: we use our heads instead? Maybe the trick is in
Speaker 1: the question. It's okay to use your head if you
Speaker 1: really are thinking. Very often we aren't. As I waited
Speaker 1: in line for the smiler with my twelve year old
Speaker 1: son snaking through the maze of concrete under the black netting,
Speaker 1: it was hard not to think about Leah Washington and
Speaker 1: her accident. Maybe all this was going through my son's
Speaker 1: mind too. As the que edged forward and his knees buckled.
Speaker 1: I'm not sure I want to do this. Come on,
Speaker 1: I said, he came all this way. It'll be sad
Speaker 1: if you don't do it. So we did it, and
Speaker 1: it was amazing. We had a great time, and he
Speaker 1: was so proud of himself. But there was one moment
Speaker 1: when we got to the front of the line, when
Speaker 1: we were offered a place on the front row. We
Speaker 1: looked at each other and shook our heads. No, not
Speaker 1: the front row, thanks, We'll sit a little bit further back.
Speaker 1: Cautionary Tales is written by me Tim Harford, with Andrew Wright,
Speaker 1: Alice Fines and Ryan Dilly. It's produced by Alice Fines
Speaker 1: and Marilyn Rust. The sound design and original music are
Speaker 1: the work of Pascal Wise. Additional sound design is by
Speaker 1: Carlos San Juan at Brain Audio Bend and daff Haffrey
Speaker 1: edited the scripts. The show features the voice talents of
Speaker 1: Melanie Guttridge, Stella Harford, a Hemborough, Sarah jupp As, Sam
Speaker 1: and Roe, Jamal Westman and Rufus Wright. The show also
Speaker 1: wouldn't have been possible without the work of Jacob Weisberg,
Speaker 1: Greta Cohene, Sarah Nix, Eric Sandler, Carrie Brody, Christina Sullivan,
Speaker 1: Kira Posey and Owen Miller. Cautionary Tales is a production
Speaker 1: of Pushkin Industries. It's recorded at Wardoor Studios in London
Speaker 1: by tom Berry. If you like the show, please remember
Speaker 1: to share, rate, and review. It really makes a difference
Speaker 1: to us and if you want to hear the show,
Speaker 1: add free sign up to Pushkin Plus on the show
Speaker 1: page on Apple Podcasts or at pushkin dot fm Slash
Speaker 1: plus eight